Fix clang-tidy util findNextTokenSkippingComments

[mbid]

Summary

The function did not update the Start source location, resulting in an
infinite loop if the first token was a comment token.

clang-tools-extra/clang-tidy/utils/LexerUtils.cpp

SourceLocation findNextTerminator(SourceLocation Start, const SourceManager &SM,
                                   const LangOptions &LangOpts) {
   return findNextAnyTokenKind(Start, SM, LangOpts, tok::comma, tok::semi);
 }
 
 Optional<Token> findNextTokenSkippingComments(SourceLocation Start,
                                               const SourceManager &SM,
                                               const LangOptions &LangOpts) {
   Optional<Token> CurrentToken;
-  do {
+  while (true) {
     CurrentToken = Lexer::findNextToken(Start, SM, LangOpts);
-  } while (CurrentToken && CurrentToken->is(tok::comment));
+    if (!CurrentToken || !CurrentToken->is(tok::comment)) {
+      break;
+    }
+    Start = CurrentToken->getLastLoc();
+  }
   return CurrentToken;
 }
 
 bool rangeContainsExpansionsOrDirectives(SourceRange Range,
                                          const SourceManager &SM,
                                          const LangOptions &LangOpts) {
   assert(Range.isValid() && "Invalid Range for relexing provided");
   SourceLocation Loc = Range.getBegin();